Berankova Katarina, Uhlik Jiri, Honkova Lenka, Pohunek Petr
Department of Paediatrics, 2nd Faculty of Medicine, Charles University and University Hospital Motol, Prague, Czech Republic.
Pediatr Allergy Immunol. 2014 Mar;25(2):136-42. doi: 10.1111/pai.12119. Epub 2013 Sep 12.
Bronchial asthma often starts in early childhood. Clinical manifestation of the disease is likely due to inflammatory processes in the airways initiated by various stimuli. Developed remodelling is regularly observed in the bronchial mucosa of adult asthmatics but we still lack information about its onset and latter development with the natural course of the disease. In this study, we analysed histological findings in bronchial biopsies obtained from very young children (under 4 yr of age). We hypothesized that initial undetectable changes in the airway epithelium of children predisposed to asthma may be one of the first mechanisms leading to morphological changes in the bronchial mucosa.
We measured the thickness of the basement membrane using a light microscope and analysed the presence of its three basic structural glycoproteins: laminin, tenascin and collagen IV, using immunohistochemical techniques. We compared these findings in children predisposed to asthma according to the selected clinical criteria of the Asthma Predictive Index and in a control group of children.
We found a significant difference in the thickness of the basement membrane between the two groups. We also found a difference in the subepithelial deposition of laminin and collagen IV in the basement membrane but no difference in the deposition of tenascin.
We conclude that initial changes leading to further remodelling may start at a very early age even before clinical manifestation of the disease.
支气管哮喘常始于儿童早期。该疾病的临床表现可能归因于各种刺激引发的气道炎症过程。在成年哮喘患者的支气管黏膜中经常观察到已形成的重塑现象，但我们仍然缺乏关于其在疾病自然进程中的起始及后续发展情况的信息。在本研究中，我们分析了从非常年幼的儿童（4岁以下）获取的支气管活检组织的组织学发现。我们推测，易患哮喘的儿童气道上皮最初难以察觉的变化可能是导致支气管黏膜形态改变的首要机制之一。
我们使用光学显微镜测量基底膜的厚度，并采用免疫组织化学技术分析其三种基本结构糖蛋白（层粘连蛋白、腱生蛋白和IV型胶原）的存在情况。我们根据哮喘预测指数的选定临床标准，将这些发现与易患哮喘的儿童以及儿童对照组进行了比较。
我们发现两组之间基底膜厚度存在显著差异。我们还发现基底膜中层粘连蛋白和IV型胶原的上皮下沉积存在差异，但腱生蛋白的沉积没有差异。
我们得出结论，导致进一步重塑的初始变化可能在疾病临床表现出现之前很早就已开始。
